Load Cell Input Module

Transcription

1 Load Cell Input Module FBs-1LC / FBs-2LC is one of the analog input modules of FATEK FBs series PLC. It supports one / two channel of load cell input for weight measurement. The conversion result is represented by a signed 16 bit integer value. In order to filter out the field noise imposed on the signal, it also provides the average of sample input function. Note: 1. The supporting of I/O configuration for FBs-1LC/2LC module is available only for PLC OS V4.71 and Winproladder V3.22 or later version. 2. For those early applications which do not use I/O configuration to work with 1LC module can still work properly provided that no additional FBs-2LC module control is required. 1 Specifications of FBs-PLC Load Cell Measurement Modules FBs-1LC/ FBs-2LC Load Cell Measurement Modules Specifications FBs-1LC FBs-2LC Total Channels one channel two channels A/D Converter Utilized 24-bit Δ-Σ A/D esolution 16 bits (include signed bit) I/O Points Occupied 1 I(Input egister) and 8 DO Conversion ate 5/ 10/ 25/ 30/ 60/ 80 Hz 1/ 3/ 5/ 8 Hz Non-Linearity 0.01% F.S. (@25 ) Zero Drift 0.2 μv/ Gain Drift 10 ppm/ Excitation Voltage 5V with 100Ω driving capability Sensitivity 2mV/V, 5mV/V, 10mV/V,20mV/V Software Filter Moving average Average Samples 1~8 configurable Isolation Transformer(Power) and photo-coupler(signal) Indicator(s) 5V PW LED Supply Power 24V-15%/+20%, 2VA Internal Power Consumption 5V, 100mA Operating Temperature 0 ~ 60 Storage Temperature -20 ~ 80 Dimensions 40(W)x90(H)x80(D) mm

2 2 The Procedures of Using FBs-PLC Load Cell Module Start Connects Load Cell Modules to the expansion interface on PLC in series and connects an external 24VDC source and load cell measure input wires. Execute the WinProladder and configure the load cell configuration table address, the register address, and working register in load cell configuration windows, then you can read the weight measurement value form register directly. 3 The Procedures of Configure the Load Cell Measurement Click the item I/O Configuration which in Project Windows: Project I/O Configuration Select LC Configuration : Once the setting page displayed, is able to measure the load cell module.

3 1. Starting register of configuration table : Assign a starting register value to store the load cell configuration table, there will allow the following inputs: XXXX or DXXXX The configuration table only occupies 4+N of registers, where N is the number of load cell modules. As shown in the above example, 5000~ 5005 stores the load cell configuration table. 2. Starting register of reading/control register : Please input the starting register number of a block register that were allocated for receiving the measurement value and control parameters for load cell There will allow the following inputs, XXXX or DXXXX one channel occupies 16 register. As shown in the above example, channel 1 used 0 ~ Starting register of working register : Assign a starting registers to reserve the working registers, there will allow the following inputs XXXX or DXXXX. The load cell measurement register occupies (Nx4)+5 registers, where N is the number of load cell modules. As shown in the above example, D0~D12 are the working registers. Notes: The above three settings can be used in all Load Cell modules. Load cell module installation information and setup 4. Module #1 ~ #16 : Display the name of the installed module and the analog starting address of its own, there are the following modules. 1 2 FBs-1LC (1 channel of load cell module) FBs-2LC (2 channels of load cell module) 5. Span Ch0# / Ch1# :Assign the following selection of the measurement range: 0~10mV(2mV/V), 0~25mV(5mV/V), 0~50mV(10mV/V), 0~100mV(20mV/V) 6. Scan ate :Assign the scan rate of reading value, there are two selections:

4 1 FBs-1LC has 5 / 10 / 25 / 30 / 60 / 80 Hz can be assigned 2 FBs-2LC has 1 / 3 / 5 / 8 Hz can be assigned 7. Times of Average :Assign the times of average for load cell measure, unbalanced average, 2 times the average, 4 times the average, and 8 times of the average can be assigned. 4 Load cell reading / control register In following table, let s assume the starting register of reading/control register is egister Description /W Offset +0 Engineering weight value +1 aw weight value +2 High reference engineering value. Max W Command register- +3 Bit 0 set zero/tare reference Bit 1 set high(full scale) reference W +4 Auto zero threshold 0~255 W +5 Status register Bit 0 Error indication Bit 1 Over range or sensor broke indication +6 SPAN value( high reference zero reference ) +7 Zero value set by performing set zero reference +8 Current compensated zero value +9 egister for internal process usage +10~+15 eserved Each channel occupies 16 registers. Note: 1. Only the register are set by user, the other register are set by system 2. +3: Bit 0 = 1, set current measurement value as zero reference Bit 1 = 1, for SPAN. set current measurement value minus zero reference value as high reference value which corresponding to the weight value set in User can convert the engineering value on their own with reference the value in +2,+6 register if necessary.

5 4. Error indication includes high reference engineering value(+2) or SPAN(+6) is zero or negative 5. Auto zeroing threshold - This value confines the zero value drift tolerance region. If the zero drift value falls in this region, the zero drift will be compensated. Set this value to zero will disable the auto zeroing function. 6. D4052 delay time for auto zeroing activation, range from 1000 ~ 5000 (ms), default is 3000 (ms).

6 5 Description of elated egisters for Load Cell Measurement Installation Status of Load Cell 4016 : B0=1 means that the 1 st channel is installed B15=1 means that the 15 th channel is installed (the default of 4016 is FFFFH) 4017 : B0=1 means that the 16 th channel is installed B15=1 means that the 31 th channel is installed (the default of 4017 is FFFFH) When the load cell is installed (the corresponding bit must be 1), the system will perform the line broken detection. If there is line broken happened, the broken value will be displayed. When the load cell is not installed (the corresponding bit must be 0), the system will not perform the line broken detection. The broken value will be 0. Depends on the user s installation, the ladder program may control the corresponding bit of 4016 and 4017 to perform or not perform the line broken detection. 6 I/O Addressing of Load Cell Module By the time domain multiplexing design method, each load cell module occupies 1 point of input register and 8 points of digital output for I/O addressing. For correct I/O access, the I/O addressing of extension modules following the load cell module must be added the I/O quantity which the corresponding module should have. The WinProladder provides an easy and convenient way to calculate the I/O address for the extension modules through the on-line I/O Numbering operation.

7 7 Wiring of Load Cell Modules Wiring of FBs-1LC 24V+ 24V- 24V +5V +EXC CH Bit Data 24-Bit Δ-Σ - A/D CH0- -EXC Load Cell

8 Wiring of FBs-2LC 24V+ 24V- 24V +5V +EXC CH0+ 16 Bit Data 24 Bit + Δ-Σ A/D - CH0- -EXC Load Cell #0 +5V +EXC 16 Bit Data 24 Bit Δ-Σ CH1+ Load Cell #1 A/D CH1- -EXC